Many musical (acoustic) drums are formed with top and bottom surfaces (or heads), separated by a cylindrical structure. The top head receives the percussion impact (e.g., from a stick or a brush), and the function of the bottom head is to reflect the vibrations from the top head, thus improving the fullness of the sound. The cylindrical shell sets the separation of the two heads and allows the pressure wave created by a drum strike to the first head to remain contained so as to produce a resonant frequency on the second head. A drum wrap may be intimately bonded to the shell (e.g., formed of a thermoformed laminated wood or plastic), and in most cases the wrap itself undergoes a thermal forming process when being attached to the cylinder.
Many typical drum shell wraps used today consist two acrylic films bonded together by an adhesive layer, and the films may range between 10-20 mil (250-500 microns), most often each at 15 mil (300 micron). The thickness of the adhesive layer may range between 1-6 mil (25-150 microns) and may be either clear or tinted or pigmented. For example, FIG. 1 shows a prior art drum wrap that includes first and second layers 10, 12 or an acrylic film (each 10-20 mil) that are bonded together by an adhesive layer 14.
While decorative wrappings on musical drums may serve decorative purposes or may be informative, for example, identifying the name of a band, it has been discovered that such drum shell wraps may also negatively impact the sound and performance of a drum.